Messages in this thread | | | Date | Fri, 25 Feb 2000 22:17:18 -0800 | From | "Jeffrey B. Siegal" <> | Subject | RE: Kernel bugs found using inspect tool |
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nathan.zook@amd.com wrote: > > if((a == b) | (c == d) | (e < f)) > > I'm right when I say "The rules have changed. Consider bit-logicals. Time > your critical inner loops". It all depends on the exact details of the code > & the processor. When c, d, e, and f are simple variables and the first two > branches are hard to predict, bit-ors should be faster on all the latest > superscalar systems.
If c, d, e and f are simple variables, then the compiler should be able to tell that it makes no difference whatsoever whether | or || is used, and should generate the same (fastest) code for both.
Unfortunately, it doesn't look like gcc (as of egcs 2.91.66) is up to the task...
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